Steward: The Hazards of Creating New Colors

Popular Mechanics, huhtikuu 1935

By Walter E. Steward

Inspecting a Pressure Mixing Chamber Used in the Manufacture of Dyes

When W. H. Perkin, a young English chemist, attempted to make some quinine in 1856 and accidentally created the first synthetic dyestuff, aniline purple, he began an era of danger to experimenters only equaled by the development of gunpowder.

It was another English scientist who discovered the composite nature of sunlight and started the train of discovery which revealed that all non-luminous and non-fluorescent substances are dependent for their color upon the light which strikes them. A red carnation appears brilliant red in red light, and yellow in yellow light, but in green or blue it appears black.

Fighting Fire Started While Making Dyestuffs

Colors of light are merely various frequencies of light waves, just as musical notes are various frequencies of soundwaves. So no man may number the colors; their number is infinity. in practical terms we recognize seven colors of the spectrum; red, orange, yellow, green, blue, indigo, and violet, and consider all others graduations of these. The painter recognizes only three colors, and calls these primary, for he has learned to blend them into any shade he desires save black and white, which he calls shadow and light, and not color.

But the dyestuff maker, by accurate mathematical computation, recognizes 4,000,000 colors, and each of these, he knows, is a precise chemical formula. Thousands have already been discovered and day by day the number is increasing.

In hundreds of dyestuff plants chemists labor to produce new colors and more permanent coloring materials. Their work is extremely dangerous, for from a group of 250 "intermediates" they may derive a possible 4,000,000 or so different chemical dyes whose properties are largely unknown until discovered by experiment.

Only a few weeks ago a chemist in a laboratory near Kearny, N. J., tarted a reaction in a glass distillation unit. Cautiously he pushed a small bunsen burner under the glass chamber. immediately the reaction began to accelerate, and he had just enough time to throw up his hands to protect his face before a violent detonation shattered the apparatus.

The Dress Derives its Color from a Coal Mine and the Test Tube of a Chemist

Dyes range in price from one dollar to over fifty dollars a pound, and it is not unusual for a new shade to result in a business for a small plant amounting to more than $100,000 in a single month.

Beginning with the distallation of the coal tar and continuing to the final grinding of the dry dyestuff, every step of the process is potentially dangerous. About a year ago, near Newark, N. J., the ordinary process of recovering benzine from coal tar was proceeding when a new workman carelessly lighted a match. With a roar heard for miles a huge steel tank sailed skyward killing four persons.

A few months later in another plant in the same vicinity one of the intermediates, benzidine, was being made by adding powdered zinc to a compound of sodium hydrozide and nitro-benzine. The mixture was in a large, lead-lined, steel tank.- A workman added the powdered zinc a little too fast, and when the reaction started the whole mass flashed over almost instantaneously. The resultant blast burst the every pressure head of the tank and sent it crashing through the heavily timbered roof.

New Fabrics Demand Hundreds of New Dye Combinations as They Are introduced

Phosgene and chlorine, both deadly gases used in chemical warfare, are used extensively in the creation of intermediates. The chlorine is fairly well controlled, but workers around the tanks where phosgene is used always wear gas masks. A few weeks ago a foreman, checking one of the phosgenation processes, came upon a worker slumped on the floor. Only quick work in getting him out and the immediate application of an oxygen respirator saved his life. investigation showed that the man had been knocked out by gas leaking into his mask through a tiny hole.

Many color are themselves colors are themselves explosive when subjected to excessive heat. Less than a year ago a small micro-mill used for grinding and mixing the dry colors became overheated, due to friction, and exploded a batch of acid anthracine brown which was in process. This color is derived from the picric acid used in gunpowder. The explosion demolished the entire end of a large building and it was only by great good fortune that the workers escaped. Accidents with this material had been so frequent that the mill was rebuilt in a bombproof shelter which was equipped with remote controls so that no one need be inside while the machinery was running.

And so the story of the creation of each new color is one of adventure and danger and high reward.

A Skein of Artificial Silk Ready For Dyeing

Above, and Optical Machine Which Classifies the New Colors as They Are Developed

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